Equalizers are used for modifying the amplitude of sound frequencies based on a listener's preferences but are not capable of being manipulated to discriminate individual sounds. As understood herein, combining frequency amplitude adjustment (to compensate for hearing impairment) with customized HRTF can be used to deliver superior sound clarity and localization for individuals who seek to experience great sound immersion, and also can be used for individuals who have hearing aids or minor hearing impairments to distinguish sounds better without modifying the spectrum of audible frequencies.
Manufacturers of hearing aids traditionally have simply modified the amplitude of all the waveforms in a collection or spectrum of sounds. This is acceptable for generalized hearing loss, but it introduces noise as well, which can make it hard to distinguish sounds as the waveforms are amplified. A much larger group of people can hear well in a quiet environment, but have trouble listening to and understanding conversations in noisy environments. These people typically suffer from partial hearing loss or find it hard to distinguish foreground sounds from background sounds.